They create a pacemaker smaller than a grain of rice

BarcelonaPacemakers help regulate the heart's rhythm when it's not beating properly, whether too fast, too slow, or irregularly. They are electronic devices that are sent running to keep the heart beating, and about 40,000 are installed in the state each year. There are several types, some of which don't even require wires or surgery to implant, and their size has been decreasing over the years. Now, researchers at Northwestern University in Evanston, United States, have developed a pioneering prototype in a study that is smaller than a grain of rice. It is a temporary device that, after its useful life, is absorbed by the patient's body, achieves effective stimulation in animals and human tissue, and could be implanted less invasively than current pacemakers, according to a study published in the journal Nature This Wednesday.

10 years ago the world's smallest pacemaker was the size of a one euro coin, about 24 millimeters. In a decade, research efforts have made it possible to reduce the size of these devices with the goal of making their implantation less invasive for patients who need them, as conventional pacemakers require open heart surgery or endovascular surgery. These are two complicated operations for both pediatric and adult patients. Therefore, American researchers have worked to make the device "extremely small," and it is now smaller than a grain of rice. Specifically, the prototype they designed measures 1.8 mm by 3.5 mm by 1 mm.

The device has electrodes that, when exposed to body fluids, generate an electrical current to make the heart beat correctly. In this way, the authors have eliminated the need for an external power source and cables, elements that other pacemakers require. Another advantage is that it is bioabsorbable, which means that when its useful life is over, it degrades automatically and no surgery is required to remove it, avoiding the patient having to go to the operating room. So far, the authors have tested it in small and large animal models, such as mice and pigs, and in human hearts from organ donors.

Experimental phase

For Julián Pérez-Villacastín, head of the cardiology department at the San Carlos Clinical Hospital in Madrid and former president of the Spanish Society of Cardiology, it is a "spectacular" prototype, but he warns that it is still in the experimental phase. "The idea is brilliant, but it will take years for this technology to be implanted in humans with sufficient guarantees," he said in statements to the Science Media Centre (SMC). However, he believes its size and the way the electrical impulses are generated to beat the heart make it a promising device. However, the authors believe the device could offer "a potentially safer alternative to larger traditional pacemakers."